I recently found a great tool to help me (or my buddy) in finding/inspecting small objects.
Jos Schulte designed an uw magifying glass that works both on dry land and down to 70m. It's quite large and offers a great view even with a mask. The focal distance is high enough to use a lamp without blinding yourself through reflections. Magnification is 2-2.5 times.
I tested the lens during several dives. The only disadvantage is the thin lanyard that comes in the box. You have to replace it because it tends to get tangled easily. I use a spiral cord with a large carabiner hook now.
My buddy watching tiny fresh water shells on a trunk.
Helge ;-)=)
The magnifier looks like an interesting gadget, but at 90 Euros (~USD 100), it's way too expensive. Edmund Scientific (www.scientificsonline.com) has tons of magnifiers at a fraction of the price.
I believe that a standard magnifying glass will not work well underwater.
For this magnifier to work, it has to have a gas filled space between two lenses. A standard magnifier needs an air/glass interface. Air has an index of refraction of about 1.0. A water/glass interface will not work too well because the index of refraction of water (1.3 I think) is too similar to the index of refraction of glass (1.53 I think).
A standard magnifier might slightly work, but not too well.
Actually, If the magnifying glass was made out of a very high index of refraction material, then it should work underwater. Maybe that is how this lens works. I have never seen one.
My buddy watching tiny fresh water shells on a trunk.
Sherlock Holmes is scuba diving
Brilliant deduction, Dr. Watson!
... but you can't imagine what you're missing to see without it.